Yesterday three physicists won the Nobel Prize in Physics for creating blue-light LEDs, which makes the LED white lights we find everywhere possible. We experience the LED revolution through computer and smartphone screens, household lighting and greenhouse grow bulbs. But for over a billion people in the world, access to light is something that they cannot rely on. One company, WakaWaka, is working to bring the LED revolution to people who live off grid and on less than $2 a day.